1. Preheat oven to 375°. Put pears in an ovenproof baking dish big enough to hold them in a single layer.
2. Whisk ancho chile and maple syrup together and drizzle over pears. Tuck in rosemary sprig.
3. Roast, uncovered, turning once, 20 to 25 minutes.
4. Remove from oven and sprinkle with salt and pepper.
Note: Nutritional analysis is per serving.